Search results for: Flat slabs and Steel fiber reinforced self compacting concrete (SFRSCC).

Authors: Samir K. Deshmukh, Mayur M. Tajane

Abstract:

In this work Membrane Distillation is applied to concentrate orange Juice. Clarified orange juice (11o Brix) obtained from fresh fruits and a sugar solution was subjected to membrane distillation. The experiments were performed on a flat sheet module using orange juice and sucrose solution as feeds. The concentration of a sucrose solution, used as a model fruit juice and also orange juice, was carried out in a direct contact membrane distillation using hydrophobic PTFE membrane of pore size 0.2 μm and porosity 70%. Surface modification of PTFE membrane has been carried out by treating membrane with alcohol and water solution to make it hydrophilic and then hydrophobicity was regained by drying. The influences of the feed temperature, feed concentration, flow rate, operating time on the permeate flux were studied for treated and non treated membrane. In this work treated and non treated membrane were compared in terms of water flux, Within the tested range, MD with surface modified membrane the water flux has been significantly improved by treating the membrane surface.

Keywords: Membrane Distillation, Surface Modification, Orange Juice. Polytetrafluoroethylene.

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Authors: José Luis Oslinger, Luis Carlos Castro

Abstract:

Measurements of capacitance C and dissipation factor tand of the stator insulation system provide useful information about internal defects within the insulation. The index k is defined as the proportionality constant between the changes at high voltage of capacitance DC and of the dissipation factor Dtand . DC and Dtand values were highly correlated when small flat defects were within the insulation and that correlation was lost in the presence of large narrow defects like electrical treeing. The discrimination between small and large defects is made resorting to partial discharge PD phase angle analysis. For the validation of the results, C and tand measurements were carried out in a 15MVA 4160V steam turbine turbogenerator placed in a sugar mill. In addition, laboratory test results obtained by other authors were analyzed jointly. In such laboratory tests, model coil bars subjected to thermal cycling resulted highly degraded and DC and Dtand values were not correlated. Thus, the index k could not be calculated.

Keywords: Aging, capacitance, dissipation factor, electrical treeing, insulation condition, partial discharge.

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Authors: R. Chimchang, R. Tongta, R. Phatthanakun

Abstract:

Inthis paper, design and fabrication of vertical micromirror for optical switching applications of single mode optical fibers are proposed. The structure of micromirror will be created from negative photoresist (SU-8) on X-ray lithography using X-ray from synchrotron light source. The properties of X-ray from synchrotron light source are high-energy electrons which can construct materials that have a high aspect ratio. In addition, the technique of gold coating of reflective material has been used for change direction of light between two pairs of optical fibers. At a wavelength of 1310 nm with minimum average loss of 5.305 dB is obtained.

Keywords: vertical micromirror, negative photoresist, X-ray lithography

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Authors: L. Marcos Domínguez, Nils Rage, Ongun B. Kazanci, Bjarne W. Olesen

Abstract:

Thermally Activated Building Systems (TABS) have proven to be an energy-efficient solution to provide buildings with an optimal indoor thermal environment. This solution uses the structure of the building to store heat, reduce the peak loads, and decrease the primary energy demand. TABS require the heated or cooled surfaces to be as exposed as possible to the indoor space, but exposing the bare concrete surfaces has a diminishing effect on the acoustic qualities of the spaces in a building. Acoustic solutions capable of providing optimal acoustic comfort and allowing the heat exchange between the TABS and the room are desirable. In this study, the effects of free-hanging units on the cooling performance of TABS and the occupants’ thermal comfort was measured in a full-scale TABS laboratory. Investigations demonstrate that the use of free-hanging sound absorbers are compatible with the performance of TABS and the occupant’s thermal comfort, but an appropriate acoustic design is needed to find the most suitable solution for each case. The results show a reduction of 11% of the cooling performance of the TABS when 43% of the ceiling area is covered with free-hanging horizontal sound absorbers, of 23% for 60% ceiling coverage ratio and of 36% for 80% coverage. Measurements in actual buildings showed an increase of the room operative temperature of 0.3 K when 50% of the ceiling surface is covered with horizontal panels and of 0.8 to 1 K for a 70% coverage ratio. According to numerical simulations using a new TRNSYS Type, the use of comfort ventilation has a considerable influence on the thermal conditions in the room; if the ventilation is removed, then the operative temperature increases by 1.8 K for a 60%-covered ceiling.

Keywords: Acoustic comfort, concrete core activation, full-scale measurements, thermally activated building systems, TRNSYS.

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Authors: D. Vidhyaprakash, A. Elango

Abstract:

In real-time applications, wheeled mobile robots are increasingly used and operated in extreme and diverse conditions traversing challenging surfaces such as a pitted, uneven terrain, natural flat, smooth terrain, as well as wet and dry surfaces. In order to accomplish such tasks, it is critical that the motion control functions without wheel slip and odometry error during the navigation of the two-wheeled mobile robot (WMR). Wheel slip and odometry error are disrupting factors on overall WMR performance in the form of deviation from desired trajectory, navigation, travel time and budgeted energy consumption. The wheeled mobile robot’s ability to operate at peak performance on various work surfaces without wheel slippage and odometry error is directly connected to four main parameters, which are the range of payload distribution, speed, wheel diameter, and wheel width. This paper analyses the effects of those parameters on overall performance and is concerned with determining the ideal range of parameters for optimum performance.

Keywords: Wheeled mobile robot (WMR), terrain, wheel slippage, odometry error, navigation.

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Authors: C. Agrawal, R. Kumar, A. Gupta, B. Chatterjee

Abstract:

An experimental investigation has been carried out to study the cooling of a hot horizontal Stainless Steel surface of 3 mm thickness, which has 800±10 C initial temperature. A round water jet of 22 ± 1 oC temperature was injected over the hot surface through straight tube type nozzles of 2.5- 4.8 mm diameter and 250 mm length. The experiments were performed for the jet exit to target surface spacing of 4 times of jet diameter and jet Reynolds number of 5000 -24000. The effect of change in jet Reynolds number on the surface quenching has been investigated form the stagnation point to 16 mm spatial location.  

Keywords: Hot-Surface, Jet Impingement, Quenching, Stagnation Point.

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Authors: Y. El Kaissi, M. Allam, A. Koulou, M. Galai, M. Ebn Touhami

Abstract:

The aim of our work is to develop an industrial bath of nickel alloy deposit on mild steel. The optimization of the operating parameters made it possible to obtain a stable Ni-P alloy deposition formulation. To understand the reaction mechanism of the deposition process, a kinetic study was performed by cyclic voltammetry and by electrochemical impedance spectroscopy (EIS). The coatings obtained have a very high corrosion resistance in a very aggressive acid medium which increases with the heat treatment.

Keywords: Ni–P coating, electrochemical impedance spectroscopy, heat treatment, cyclic voltammetry, potentiodynamic polarization.

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Authors: Kyomin Lee, Joohee Kim, Sangho Kang

Abstract:

The commercial nuclear power reactor in South Korea, Kori Unit 1, which was a 587 MWe pressurized water reactor that started operation since 1978, was permanently shut down in June 2017 without an additional operating license extension. The Kori 1 Unit is scheduled to become the nuclear power unit to enter the decommissioning phase. In this study, the preliminary evaluation of the decommissioning wastes for the Kori Unit 1 was performed based on the following series of process: firstly, the plant inventory is investigated based on various documents (i.e., equipment/ component list, construction records, general arrangement drawings). Secondly, the radiological conditions of systems, structures and components (SSCs) are established to estimate the amount of radioactive waste by waste classification. Third, the waste management strategies for Kori Unit 1 including waste packaging are established. Forth, selection of the proper decontamination and dismantling (D&D) technologies is made considering the various factors. Finally, the amount of decommissioning waste by classification for Kori 1 is estimated using the DeCAT program, which was developed by KEPCO-E&C for a decommissioning cost estimation. The preliminary evaluation results have shown that the expected amounts of decommissioning wastes were less than about 2% and 8% of the total wastes generated (i.e., sum of clean wastes and radwastes) before/after waste processing, respectively, and it was found that the majority of contaminated material was carbon or alloy steel and stainless steel. In addition, within the range of availability of information, the results of the evaluation were compared with the results from the various decommissioning experiences data or international/national decommissioning study. The comparison results have shown that the radioactive waste amount from Kori Unit 1 decommissioning were much less than those from the plants decommissioned in U.S. and were comparable to those from the plants in Europe. This result comes from the difference of disposal cost and clearance criteria (i.e., free release level) between U.S. and non-U.S. The preliminary evaluation performed using the methodology established in this study will be useful as a important information in establishing the decommissioning planning for the decommissioning schedule and waste management strategy establishment including the transportation, packaging, handling, and disposal of radioactive wastes.

Keywords: Characterization, classification, decommissioning, decontamination and dismantling, Kori 1, radioactive waste.

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Authors: Leila Graini

Abstract:

In this paper, we demonstrate basic all-optical functions for 2R regeneration (Re-amplification and Re-shaping) based on self-similar spectral broadening in low normal dispersion and highly nonlinear fiber (ND-HNLF) to regenerate the signal through optical filtering including the transfer function characteristics, and output extinction ratio. Our approach of all-optical 2R regeneration is based on those of Mamyshev. The numerical study reveals the self-similar spectral broadening very effective for 2R all-optical regeneration; the proposed design presents high stability compared to a conventional regenerator using SPM broadening with reduction of the intensity fluctuations and improvement of the extinction ratio.

Keywords: All-optical function, 2R optical regeneration, self-similar broadening, Mamyshev regenerator.

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Authors: Inwon Lee, Victor M. Kulik, Andrey V. Boiko, Ho Hwan Chun

Abstract:

A specially designed flat plate was mounted vertically over the axial line in the wind tunnel of the Aerospace Department of the Pusan National University. The plate is 2 m long, 0.8 m high and 8 cm thick. The measurements were performed in velocity range from 15 to 60 m/s. A sand paper turbulizer was placed close to the plate nose to provide fully developed turbulent boundary layer over the most part of the plate. Strain balances were mounted in the trailing part of the plate to measure the skin friction drag over removable insertions of 0.55×0.25m2 size. A set of the insertions was designed and manufactured: 3mm thick polished metal surface and three compliant surfaces. The compliant surfaces were manufactured of a silicone rubber Silastic® S2 (Dow Corning company). To modify the viscoelastic properties of the rubber, its composition was varied: 90% of the rubber + 10% catalyst (standard), 92.5% + 7.5% (weak), 85% + 15% (strong). Modulus of elasticity and the loss tangent were measured accurately for these materials in the frequency range from 40 Hz to 3 KHz using the unique proposed technique.

Keywords: boundary layer, compliant coating, drag reduction, hot wire, wind tunnel.

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Authors: A. Alshebani, Y. Swesi, S. Mrayed, F. Altaher, I. Musbah

Abstract:

Cs-type nanocomposite zeolite membrane was successfully synthesized on an alumina ceramic hollow fibre with a mean outer diameter of 1.7 mm; cesium cationic exchange test was carried out inside test module with mean wall thickness of 230 μm and an average crossing pore size smaller than 0.2 μm. Separation factor of n-butane/H₂ obtained indicate that a relatively high quality closed to 20. Maxwell-Stefan modeling provides an equivalent thickness lower than 1 µm. To compare the difference an application to CO₂/N₂ separation has been achieved, reaching separation factors close to (4,18) before and after cation exchange on H-zeolite membrane formed within the pores of a ceramic alumina substrate.

Keywords: MFI membrane, nanocomposite, Ceramic hollow fibre, CO2, Ion-exchange.

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Authors: Bassam M. Abunahel, Nurul Zahirah Noor Azman, Munirah Jamil

Abstract:

The effect of needle diameter on the morphological structure of electrospun n-Bi₂O₃/epoxy-PVA nanofibers has been investigated using three different types of needle diameters. The results were observed and investigated using two techniques of scanning electron microscope (SEM). The first technique is backscattered SEM while the second is secondary electron SEM. The results demonstrate that there is a correlation between the needle diameter and the morphology of electrospun nanofibers. As the internal needle diameter decreases, the average nanofiber diameter decreases and the fibers get thinner and smoother without agglomeration or beads formation. Moreover, with small needle diameter the nanofibrous porosity get larger compared with large needle diameter.

Keywords: Needle diameter, fiber diameter, agglomeration, porosity, SEM.

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Authors: J. Alizadeh K., R. S. Ashofteh, A. Asadi Lari

Abstract:

Railway vehicle wheels are designed to operate in harsh environments and to withstand high hydrostatic contact pressures. This situation may result in critical circumstances, in particular wheel breakage. This paper presents a time history of a series of broken wheels during a time interval [2007-2008] belongs to locomotive fleet on Iranian Railways. Such fractures in locomotive wheels never reported before. Due to the importance of this issue, a research study has been launched to find the potential reasons of this problem. The authors introduce a FEM model to indicate how and where the wheels could have been affected during their operation. Then, the modeling results are presented and discussed in detail.

Keywords: Crack, fatigue, FE analysis, wheel.

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Authors: Trevor Sabiston, Mohsen Mohammadi, Mohammed Cherkaoui, Kaan Inal

Abstract:

A new micromechanics framework is developed for long fibre reinforced composites using a single fibre surrounded by a functionally graded interphase and matrix as a representative unit cell. The unit cell is formulated to represent any number of aligned fibres by a single fibre. Using this model the elastic response of long fibre composites is predicted in all directions. The model is calibrated to experimental results and shows very good agreement in the elastic regime. The differences between the proposed model and existing models are discussed.

Keywords: Computational mechanics, functionally graded interphase, long fibre composites, micromechanics.

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Authors: M. A. Elbagermia, A. I. Alajtala, M. Alkerzab

Abstract:

This study compares the quality of different brands of Portland Cement (PC) available in Libyan market. The amounts of chemical constituents like SiO2, Al2O3, Fe2O3, CaO, MgO, SO3 and Lime Saturation Factor (LSF) were determined in accordance with Libyan (L.S.S) and Amrican (A.S.S) Standard Specifications. All the cement studies were found to be good for concrete work especially where no special property is required. The chemical and mineralogical analyses for studied clinker samples show that the dominant phases composition are C3S and C2S while the C3A and C4AF are less abundant.

Keywords: Portland cement, Chemical Composition, Libyan market, X-ray fluorescence.

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Authors: Carsten Röcker

Abstract:

This paper presents a set of guidelines for the design of multi-user awareness systems. In a first step, general requirements for team awareness systems are analyzed. In the second part of the paper, the identified requirements are aggregated and transformed into concrete design guidelines for the development of team awareness systems.

Keywords: User Interface Design, Awareness Systems, User- Centered Design, Human Factors.

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Authors: Andrey V. Timofeev, Dmitry V. Egorov, Viktor M. Denisov

Abstract:

This paper presents development results of usage of C-OTDR monitoring systems for rail traffic management. The COTDR method is based on vibrosensitive properties of optical fibers. Analysis of Rayleigh backscattering radiation parameters changes which take place due to microscopic seismoacoustic impacts on the optical fiber allows to determine seismoacoustic emission source positions and to identify their types. This approach proved successful for rail traffic management (moving block system, weigh- in-motion system etc.).

Keywords: C-OTDR systems, moving block-sections, rail traffic management, Rayleigh backscattering, weigh-in-motion.

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Authors: Josef Fládr, Jiří Němeček, Veronika Koudelková, Petr Bílý

Abstract:

Mechanical parameters of cementitious composites differ quite significantly based on the composition of cement matrix. They are also influenced by mixing times and procedure. The research presented in this paper was aimed at identification of differences in microstructure of normal strength (NSC) and differently mixed high strength (HSC) cementitious composites. Scanning electron microscopy (SEM) investigation together with energy dispersive X-ray spectroscopy (EDX) phase analysis of NSC and HSC samples was conducted. Evaluation of interfacial transition zone (ITZ) between the aggregate and cement matrix was performed. Volume share, thickness, porosity and composition of ITZ were studied. In case of HSC, samples obtained by several different mixing procedures were compared in order to find the most suitable procedure. In case of NSC, ITZ was identified around 40-50% of aggregate grains and its thickness typically ranged between 10 and 40 µm. Higher porosity and lower share of clinker was observed in this area as a result of increased water-to-cement ratio (w/c) and the lack of fine particles improving the grading curve of the aggregate. Typical ITZ with lower content of Ca was observed only in one HSC sample, where it was developed around less than 15% of aggregate grains. The typical thickness of ITZ in this sample was similar to ITZ in NSC (between 5 and 40 µm). In the remaining four HSC samples, no ITZ was observed. In general, the share of ITZ in HSC samples was found to be significantly smaller than in NSC samples. As ITZ is the weakest part of the material, this result explains to large extent the improved mechanical properties of HSC compared to NSC. Based on the comparison of characteristics of ITZ in HSC samples prepared by different mixing procedures, the most suitable mixing procedure from the point of view of properties of ITZ was identified.

Keywords: Energy dispersive X-ray spectroscopy, high strength concrete, interfacial transition zone, mixing procedure, normal strength concrete, scanning electron microscopy.

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Authors: Changyi Liu, Gui Wang, Matthew Dargusch

Abstract:

Helical milling operations are used to generate or enlarge boreholes by means of a milling tool. The bore diameter can be adjusted through the diameter of the helical path. The kinematics of helical milling on a three axis machine tool is analysed firstly. The relationships between processing parameters, cutting tool geometry characters with machined hole feature are formulated. The feed motion of the cutting tool has been decomposed to plane circular feed and axial linear motion. In this paper, the time varying cutting forces acted on the side cutting edges and end cutting edges of the flat end cylinder miller is analysed using a discrete method separately. These two components then are combined to produce the cutting force model considering the complicated interaction between the cutters and workpiece. The time varying cutting force model describes the instantaneous cutting force during processing. This model could be used to predict cutting force, calculate statics deflection of cutter and workpiece, and also could be the foundation of dynamics model and predicting chatter limitation of the helical milling operations.

Keywords: Helical milling, Hole machining, Cutting force, Analytical model, Time domain

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Authors: M.A. Kamely, M.Y. Noordin

Abstract:

A judicious choice of insert material, tool geometry and cutting conditions can make hard turning produce better surfaces than grinding. In the present study, an attempt has been made to investigate the effect of cutting tool materials on cutting forces (feed force, thrust force and cutting force) in finish hard turning of AISI D2 cold work tool steel. In conclusion of the results obtained with a constant depth of cut and feed rate, it is important to note that cutting force is directly affected by cutting tool material.

Keywords: hard turning, cutting force, cutting tool materials, mixed ceramic, cbn

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Authors: H. Pahlavanzadeh, A.R.Jahangiri, I. Noshadi

Abstract:

In this paper, the solubility of CO2 in AMP solution have been measured at temperature range of ( 293, 303 ,313,323) K.The amine concentration ranges studied are (2.0, 2.8, and 3.4) M. A solubility apparatus was used to measure the solubility of CO2 in AMP solution on samples of flue gases from Thermal and Central Power Plants of Esfahan Steel Company. The modified Kent Eisenberg model was used to correlate and predict the vapor-liquid equilibria of the (CO2 + AMP + H2O) system. The model predicted results are in good agreement with the experimental vapor-liquid equilibrium measurements.

Keywords: AMP, Carbon dioxide; loading, Flue gases, Modified Kent Eisenberg model

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Authors: M.H.R.O. Abdullah, P.E. Ch'ng, N.A. Yunus

Abstract:

Some physical properties of musk lime (Citrus microcarpa) were determined in this study. The average moisture content (wet basis) of the fruit was found to be 85.10 (±0.72) %. The mean of length, width and thickness of the fruit was 26.36 (±0.97), 26.40 (±1.04) and 25.26 (±0.94) mm respectively. The average value for geometric mean diameter, sphericity, aspect ratio, mass, surface area, volume, true density, bulk density and porosity was 26.00 (±0.82) mm, 98.67 (±2.04) %, 100.23 (±3.28) %, 10.007 (±0.878) g, 2125.07 (±133.93) mm2, 8800.00 (±731.82) mm3, 1002.87 (±39.16) kgm-3, 501.70 (±22.58) kgm-3 and 49.89 (±3.15) % respectively. The coefficient of static friction on four types of structural surface was found to be varying from 0.238 (±0.025) for glass to 0.247 (±0.024) for steel surface.

Keywords: Musk lime, Citrus microcarpa, physical properties.

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Authors: Kedit J.

Abstract:

This paper is the tomographic images reconstruction simulation for defects detection in specimen. The specimen is the thin cylindrical steel contained with low density materials. The defects in material are simulated in three shapes.The specimen image function will be transformed to projection data. Radon transform and its inverse provide the mathematical for reconstructing tomographic images from projection data. The result of the simulation show that the reconstruction images is complete for defect detection.

Keywords: Tomography, Tomography Reconstruction, Radon Transform

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Authors: Fatma Khaled, Khaoula Hidouri, Bechir Chaouachi

Abstract:

Desalination using solar energy coupled with membrane techniques such as vacuum membrane distillation (VMD) is considered as an interesting alternative for the production of pure water. During this work, a developed model of a polytetrafluoroethylene (PTFE) hollow fiber membrane module of a VMD unit of seawater was carried out. This simulation leads to establishing a comparison between the effects of two different equations of the vaporization latent heat on the membrane surface temperature and on the unit productivity. Besides, in order to study the effect of putting membrane modules in series on the outlet fluid temperature and on the productivity of the process, a simulation was executed.

Keywords: Vacuum membrane distillation, membrane module, membrane temperature, productivity.

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Authors: V. K. Nelson, S. Karthikeyan

Abstract:

Axisymmetric vibration of an infinite Pyrocomposite circular hollow cylinder made of inner and outer pyroelectric layer of 6mm-class bonded together by a Linear Elastic Material with Voids (LEMV) layer is studied. The exact frequency equation is obtained for the traction free surfaces with continuity condition at the interfaces. Numerical results in the form of data and dispersion curves for the first and second mode of the axisymmetric vibration of the cylinder BaTio3 / Adhesive / BaTio3 by taking the Adhesive layer as an existing Carbon Fibre Reinforced Polymer (CFRP) are compared with a hypothetical LEMV layer with and without voids and as well with a pyroelectric hollow cylinder. The damping is analyzed through the imaginary parts of the complex frequencies.

Keywords: Axisymmetric vibration, CFRP, hollow cylinders, LEMV, pyrocomposite

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Authors: Hesham A. Ali, Mofreh M. Salem, Ahmed A. Hamza

Abstract:

Recently, there have been considerable efforts towards the convergence between P2P and Grid computing in order to reach a solution that takes the best of both worlds by exploiting the advantages that each offers. Augmenting the peer-to-peer model to the services of the Grid promises to eliminate bottlenecks and ensure greater scalability, availability, and fault-tolerance. The Grid Information Service (GIS) directly influences quality of service for grid platforms. Most of the proposed solutions for decentralizing the GIS are based on completely flat overlays. The main contributions for this paper are: the investigation of a novel resource discovery framework for Grid implementations based on a hierarchy of structured peer-to-peer overlay networks, and introducing a discovery algorithm utilizing the proposed framework. Validation of the framework-s performance is done via simulation. Experimental results show that the proposed organization has the advantage of being scalable while providing fault-isolation, effective bandwidth utilization, and hierarchical access control. In addition, it will lead to a reliable, guaranteed sub-linear search which returns results within a bounded interval of time and with a smaller amount of generated traffic within each domain.

Keywords: Grid computing, grid information service, P2P, resource discovery.

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Authors: Tomáš Korecký, Kamil Ďurana, Miroslava Lapková, Robert Černý

Abstract:

Method of determining of moisture diffusivity on two types of autoclaved aerated concretes with different bulk density is represented in the paper. On the specimens were measured one dimensional water transport only on liquid phase. Ever evaluation was done from moisture profiles measured in specific times by capacitance moisture meter. All values from capacitance meter were recalculated to moisture content by mass. Moisture diffusivity was determined in dependence on both moisture and temperature. The experiment temperatures were set at values 55, 65, 75 and 85°C.

Keywords: moisture diffusivity, autoclaved aerated concrete, capacitance moisture meter

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Authors: Parastou Kharazmi, Folke Björk

Abstract:

Some of the main causes for degradation of polymeric materials are thermal aging, hydrolysis, oxidation or chemical degradation by acids, alkalis or water. The first part of this paper provides a brief summary of advances in technology, methods and specification of composite materials for relining as a rehabilitation technique for sewage systems. The second part summarizes an investigation on frequently used composite materials for relining in Sweden, the rubber filled epoxy composite and reinforced polyester composite when they were immersed in deionized water or in dry conditions, and elevated temperatures up to 80°C in the laboratory. The tests were conducted by visual inspection, microscopy, Dynamic Mechanical Analysis (DMA), Differential Scanning Calorimetry (DSC) as well as mechanical testing, three point bending and tensile testing.

Keywords: Composite, epoxy, polyester, relining, sewage.

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Authors: K. Rattawan, W. Intagun, W. Kanoksilapatham

Abstract:

Objective of this research is to study effect of coffee grounds on physical and heating value properties of sugarcane bagasse pellets. The coffee grounds were tested as an additive for pelletizing process of bagasse pellets. Pelletizing was performed using a Flat–die pellet mill machine. Moisture content of raw materials was controlled at 10-13%. Die temperature range during the process was 75-80 ^oC. Physical characteristics (bulk density and durability) of the bagasse pellet and pellets with 1-5% coffee ground were determined following the standard assigned by the Pellet Fuel Institute (PFI). The results revealed increasing values of 648±3.4, 659 ± 3.1, 679 ± 3.3 and 685 ± 3.1 kg/m³ (for pellet bulk density); and 98.7 ± 0.11, 99.2 ± 0.26, 99.3 ± 0.19 and 99.4 ± 0.07% (for pellet durability), respectively. In addition, the heating values of the coffee ground supplemented pellets (15.9 ± 1.16, 17.0 ± 1.23 and 18.8 ± 1.34 MJ/kg) were improved comparing to the non-supplemented control (14.9 ± 1.14 MJ/kg), respectively. The results indicated that both the bulk density and durability values of the bagasse pellets were increased with the increasing proportion of the coffee ground additive.

Keywords: Bagasse, coffee grounds, pelletizing, heating value, sugar cane bagasse.

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Authors: Takaharu Miyoshi, Tadahiko Higuchi

Abstract:

Education supported by mobile computers has been widely done for some time. Teachers have attempted to use mobile computers and to find concrete subjects for student-s fieldwork training in college education. The purpose of this research is to develop software for Personal Digital Assistant (PDA) to conduct fieldwork in our campus, and to report a fieldwork class using PDAs in the curriculum of the Department of Regional Environment Studies.

Keywords: Development of software for PDA, fieldwork training, computer supported education, experiential learning.

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